Method for fabricating crystalline-dielectric thin films and devices formed using same

ABSTRACT

This invention describes a new method for forming and depositing thin films of crystalline dielectric materials. The present technique uses chemical synthesis to control the granularity and thickness of the dielectric films. This method has several key advantages over existing technologies, and facilitates the integration of crystalline dielectric materials into high-density memory devices.

This invention relates to a method for forming and depositing thin filmsof crystalline dielectric materials on a substrate, and devices formedusing this thin film technique. The thin film devices are made by themethod of the invention and form a part of a variety of thin filmdevices, such as, capacitors, field effect transistors, memory devicesand the like.

BACKGROUND OF THE INVENTION

In recent years there has been significant effort focused on integratingperovskite-type insulators (most notably Barium Strontium Titanate, orBST) into high-density DRAM memory structures. These materials arecrystalline dielectric materials, which exhibit large dielectricresponses (relative to conventional amorphous dielectric materials, suchas SiO₂) due to ionic displacements within their crystal lattice.Similarly, there have been renewed efforts to develop viablehigh-density, non-volatile memory circuits based on ferroelectricdielectric materials. Ferroelectric materials are also crystallinedielectric materials and also possess the additional property of apermanent electric dipole moment whose orientation direction can bechanged with an external electric field. From a fabrication standpoint,combining these crystalline dielectric materials with silicon processingposes serious difficulties. For example, forming the proper crystalstructure (to obtain desired dielectric properties) requires highprocessing temperatures, which can have a detrimental effect on otherparts of the circuit. Also, because these dielectric materials arecrystalline, a film thereof has a grain structure and orientation thatplay a crucial role in determining device characteristics, such asleakage and polarization.

Recent work has shown that the grain size in crystalline dielectricfilms (in particular, much work has been done on BST) can be influencedsomewhat by film deposition conditions. Upon crystallization to thehigh-dielectric phase, some films can become quite porous. Voids betweengrains in the dielectric can cause electrical shorts for sufficientlythin films. Problems associated with film grain size have becomeimportant as attempts are made to fabricate devices that are roughly thesame size as the film granularity. These problems can be demonstratedwith an example of a high density memory device.

Referring to FIG. 1, a high density memory device 10 includes atransistor 12 disposed below a capacitor 14. Transistor 12 and capacitor14 are connected through a polycrystalline silicon (poly-Si) plug 16.The capacitor contains a crystalline dielectric material. FIG. 2 shows adifficulty in fabricating high density memory device 10. In order toobtain the proper crystal phase (with desirable properties) of thecrystalline dielectric material, it is often necessary to subject thecrystalline dielectric material to a high-temperature (>600° C.) annealin oxygen. However, this process is detrimental to the rest ofhigh-density memory device 10, because at high temperature, the oxygendiffuses down to and oxidizes poly-Si plug 16 it, converting it from aconductor to an insulator, thereby rendering high density memory device10 inoperable.

Efforts have been made to develop a conducting barrier layer to placebetween a bottom electrode of capacitor 14 and poly-Si plug 16. Therequirements for such a barrier are stringent, i.e., it must beelectrically conducting, stop oxygen diffusion, and be non-reactive withoxygen at temperatures up to >600° C. These problems are major obstaclesto the development high-density memory devices using crystallinedielectric materials.

SUMMARY OF THE INVENTION

The present invention pertains to a method for fabricating a thin filmon a substrate. A plurality of nanoparticles that is initially in asolvent is deposited on the substrate in such a way that thenanoparticles form a monolayer on the substrate. The nanoparticles arecoated with an organic surfactant and are electrically insulating withrelative dielectric constant greater than 10. The percentage of the thinfilm comprised of nanoparticles is preferably in a range of about 50% toabout 100%.

The nanoparticles preferably have a diameter size in the range betweenabout 2 nm to about 20 nm. In another embodiment, the distribution ofthe diameter size in the thin film has a standard deviation selectedfrom the group consisting of: less than 15%, less than 10% and less than5%.

In another embodiment of the method of the invention, the nanoparticlesare deposited from a solvent solution onto a liquid subphase. Thesolvent is then evaporated so that a closely packed monolayer of thenanoparticles is formed at the subphase liquid to air interface. Adeposition step then transfers the closely packed monolayer ofnanoparticles to the substrate.

In another embodiment of the method of the invention, the nanoparticlesare heated or sintered after deposition on the substrate to form thethin film. Preferably, the surfactant is removed by the heating step.

The heating is carried out in a temperature range of preferably about100°C. to about 800° C. and more preferably about 300° C. to about 650°C. The heating is carried out using a conventional oven or furnace,rapid thermal processing (RTA) or irradiation from a laser, a microwave,an electron beam or an ion beam.

Preferably, the above mentioned steps of depositing the nanoparticles onthe substrate and heating the substrate and nanoparticles are repeatedto increase thickness of the thin film.

Preferably, the nanoparticles are composed of a perovskite-type oxidehaving the formula ABO₃, wherein A is at least one additional cationhaving a positive formal charge in the range between about 1 to about 3;and wherein B is at least one acidic oxide containing a metal selectedfrom Group IVB, VB, VIB, VIIB, IIIA, and IB metals.

The nanoparticles are preferably a pervoskite-type oxide selected fromthe group consisting of: a titanate-based ferroelectric, amanganate-based material, a cuprate based material, a tungstenbronze-type niobate, tantalate or titanate, or a layer bismuthtantalate, niobate, or titanate.

The nanoparticles are optionally a ferroelectric material selected fromthe group consisting of: bismuth titanate, strontium bismuth tantalate,strontium bismuth niobate, strontium bismuth tantalate niobate, leadzirconate titanate, lead lanthanum zirconate titanate, lead titanate,bismuth titanate, lithium niobate, lithium tantalate, strontiumrhuthenate, barium titanite, strontium titanate and compositions ofthese materials modified by incorporation of a dopant.

The nanoparticles are preferably formed with a non-aqueous chemicalprocess that injects metal oxide precursors at temperatures in the rangebetween about 60° C. to about 300° C. or the precursors are added at lowtemperature and then heated to between about 60° C. to about 300° C.

In other embodiments, the nanoparticles are formed in a predeterminedcrystalline phase by synthesis or heating.

The solvent is preferably a material with an end functional groupselected from the radical consisting of: —COO—, —CON—, —CN, —NC, —S—,—O—, —N—, —P—, —C═C—, and —C≡C—. The solvent is preferably evaporated attemperatures in the range between about 0° C. to about 150° C., morepreferably between about 20° C. to about 40° C.

The solvent is preferably selected from the group consisting of: ethers,alcohols, arenes, chlorinated, fluorinated, —COO—, —CON—, —CN—, NC—,—S—, —O—, —N— and —P—.

The thin film produced according to the present invention can be used tofabricate capacitors, field effect transistors and other devices.

BRIEF DESCRIPTION OF THE DRAWING

Other and further objects, advantages and features of the presentinvention will be understood by reference to the following specificationin conjunction with the accompanying drawings, in which like referencecharacters denote like elements of structure and:

FIG. 1 is a side-view of a conventional high-density memory device;

FIG. 2 shows the device of FIG. 1 being subjected to a high-temperatureoxygen anneal;

FIG. 3 is a side view of a thin film device of the present invention inan intermediate process form;

FIG. 4 is a top view of FIG. 3;

FIG. 5 is a side view of a thin film device of the present invention inan intermediate process form;

FIG. 6 is a top view of FIG. 5;

FIG. 7 is a side view of a thin film device of the present invention inan intermediate process form;

FIG. 8 is a top view of FIG. 7;

FIG. 9 is a side view of a thin film device of the present invention inan intermediate process form;

FIG. 10 is a top view of FIG. 9;

FIG. 11 is a side view of a thin film device of the present invention inan intermediate process form;

FIG. 12 is a top view of FIG. 11;

FIG. 13 is a side view of a thin film device of the present invention;

FIG. 14 is a top view of FIG. 13;

FIG. 15 is a side view of a thin film device of the present invention inan intermediate process form;

FIG. 16 is a top view of FIG. 15;

FIG. 17 is a side view of a thin film device of the present invention inan intermediate process form;

FIG. 18 is a top view of FIG. 17;

FIG. 19 is a side view of a thin film device of the present invention inan intermediate process form;

FIG. 20 is a top view of FIG. 19;

FIG. 21 is a side view of a thin film device of the present invention inan intermediate process form;

FIG. 22 is a top view of FIG. 21;

FIG. 23 is a side view of a thin film device of the present invention;and

FIG. 24 is a top view of FIG. 23.

DETAILED DESCRIPTION OF THE INVENTION

A method is provided for processing crystalline dielectric materials,which avoids several of the problems hindering their integration intostandard silicon processes. The present invention can be used tofacilitate the integration of ferroelectric thin films, as well as othercrystalline dielectrics, such as BST.

The chemistry of preparing an initial solution for the present methodinvolves adjusting the chemical conditions to control the maximum sizeof the nanoparticles, and also to prevent them from agglomerating, andby coating the nanoparticles with an organic layer. Once the reaction iscomplete, the nanoparticles can be size-selected using well knowncentrifuge techniques. This results in a solution containing isolated,highly uniform nanoparticles of the appropriate composition.

In general, the nanoparticles for the present invention are uniformlysized and shaped in a range of about 2-50 nm and also exhibit highpolarizability (with or without hysteresis). The nanoparticles have oradopt crystalline structures that are noncentrosymmetric and thatdisplay high polarizability due largely to a systematic distortion ofthe ionic lattice (i.e., distinct from limited polarization obtained inmaterials where only the electron distribution is distorted). Thedielectric nanoparticles are not being limited to the perovskite familyof structures, although the preferred embodiments feature this family.In the preferred embodiment, BaTiO₃ and BaxSr(1−x)TiO₃, adopt either thecubic 3 mm structure in the non-ferroelectric state, or the 4 mmtetragonal modification of the perovskite structure when in theferroelectric state. Nanoparticles 20 may be composed of ferroelectricmaterial including a perovskite-types oxide having the formula ABO₃wherein A is at least one additional cation having a positive formalcharge of from about 1 to about 3, and B is at least one acidic oxidecontaining at least one metal selected from the group consisting of:Group IVB, VB, VIB, VIIB, IIIA and IB metals of the Periodic Table ofElements. The perovskite-type oxide can also be at least one materialselected from the group consisting of: a titanate-based ferroelectric, amanganate-based material, a cuprate based material, a tungstenbronze-type niobate, tantalate or titanate, or a layered bismuthtantalate, niobate, titanate; and more specifically, bismuth titanate,strontium bismuth tantalate, strontium bismuth niobate, strontiumbismuth tantalate niobate, lead zirconate titanate, lead lanthanumzirconate titanate, lead titanate, bismuth titanate, lithium niobate,lithium tantalate, strontium rhuthenate, and compositions of thesematerials modified by incorporation of a dopant.

Nanoparticles composed of, for example, crystalline dielectricmaterials, are prepared in solution using chemical synthesis techniques.Starting with nanoparticles in solution, a thin-film is prepared bydip-coating a substrate with a nanoparticle monolayer formed on a liquidsubphase (often referred to as a Langmuir-Blodgett technique).

Referring to FIGS. 3 and 4, a liquid subphase 40 is prepared. Thissubphase 40 may include water, ethylene glycol, propylene glycol, ormixtures thereof. Referring to FIGS. 5 and 6, nanoparticles 20 aredeposited from the initial solution onto liquid subphase 40. Afterevaporation of the nanoparticle solvent, nanoparticles 20 are confinedto the liquid-air interface (i.e., they float on the liquid). Thenanoparticle solvent may include hexane, toluene, octane, chloroform ormethylene chloride, as well as other suitable organic solvents.Nanoparticles 20 have been previously coated with an organic coating orsurfactant 22, which prevents them from aggregating. Possible organicsurfactants or stabilizers include molecules with end functional groupsselected from the group consisting of: —COO— (e.g., RCOOH), —CON— (e.g.,RCONH₂), —CN (e.g., RCN), —NC (RNC), —S— (e.g., RSH), —O— (e.g., ROH),—N— (e.g., R₃N), and —P— (e.g., R₃P) units, wherein R represents ahydrocarbon chain. In some circumstances, it may be advantageous toincorporate functional groups, such as C—C double bond (e.g.,R1—CH═CH—R₂), C≡C triple bond (e.g., R1—C—C—R₂), —COO— (e.g.,R₁—COO—R₂), —CON— (e.g., R1—CONH—R₂), —S— (e.g., R₁—S—R₂), —O— (e.g.,R₁—O—R₂), —N— (e.g., R₁—NH—R₂), or —P— (e.g., R₁—PH—R₂) type unit(s),where R₁ represent the hydrocarbon chain, while R₂ contains the endfunctional groups such as RCOOH, RCONH₂, RCN, RSH, ROH, into thestabilizer to enhance the film forming process. Techniques for attachingthe stabilizer(s) or the organic surfactants to the nanoparticlesinclude formation of chemical or physical bonds between thenanoparticles and the stabilizer(s).

Referring to FIGS. 7-10, compression of nanoparticles 20 on liquidsubphase 40 packs them into an ordered monolayer 42, covering largeareas with minimal space between nanoparticles 20. Monolayer 42 is thentransferred onto a solid substrate 46 (FIG. 8), such as by dipping thesolid substrate 46 onto liquid subphase 40.

Referring to FIGS. 9-14, annealing substrate 46 that contains monolayer42 at high temperature removes organic surfactant 22 and sintersnanoparticles 20 together into a continuous film 30. Because of thelarge nanoparticle surface area, the sintering temperatures are reducedbelow that of a bulk material. Sintering of the films is carried out attemperatures in the range of between about 100° C. to about 800° C.Optimally, the films made according to the method of the presentinvention will be processed at lower temperatures for maximum benefitfor integration of the materials with device designs. The preferredannealing/sintering conditions will be in an atmosphere with an inertgas (nitrogen, argon, helium) and oxygen. A temperature range of betweenabout 300 to about 650° C. is preferred, which is just below thetemperature in which annealing conventional devices in oxygen causesserious failures as described above with respect to FIGS. 1 and 2.

In another embodiment of the invention, referring to FIGS. 15-24,nanoparticles 20 are dispersed into a carrier solvent 50 andsubsequently deposited onto a substrate 52. Substrate 52 may be heated(or kept at room temperature) to allow solvent 50 to evaporate.Evaporation of the carrier solvent 50 from the dispersion is carried outat temperatures in a range of 0° C. and 150° C., with a most desirabletemperature range of about 20° C. to about 40° C. The temperature isselected to correlate with the volatility of the carrier solvent 50 sothat the deposition of the film occurs in a period of between about 30seconds to about 30 minutes with times in a range of between about 1 toabout 10 minutes being most preferred (i.e., lower temperatures for morevolatile solvents, high temperatures for less volatile solvents). If theevaporation is too rapid, it has been found that the resulting particlefilm is poorly ordered, and often exhibits significant porosity and ahigh level of defects, voids and cracks. If the drying is too slow theprocess time becomes inconvenient, increasing cost, but there is noupper limit on the time of evaporation for film quality. Generally, thesolvent can be of any kind that can dissolve/disperse the particles;including solvents such as water, alcohol, an alkane (e:g., pentane,hexane, heptane, octane, etc.), an arene (e.g., benzene, toluene,seitylene, etc.), a chlorinated solvent (e.g., methylene chloride,chloroform, etc.) and the type with unit of —COO— (e.g., CH₃COOC₂H₅),—CON— (e.g., CH₃CONHC₂H₅), —CN (e.g., CH₃CN), —NC (e.g., CH₃COOC₂H₅),—S— (e.g., C₄H₉SC₄H₉), —O— (e.g., C₂H₅OC₂H₅, —N— (e.g C₄H₉NH₂), or —P—(e.g., (C₄H₉)3P).

After solvent 50 evaporates, the remaining nanoparticles 20 arecondensed into a close-packed arrangement on the surface of substrate52. The next step anneals substrate 52 containing the nanoparticlemonolayer 42 at a high temperature. This removes organic surfactant 22surrounding nanoparticles 20 and sinters them together into a continuousfilm 54. Because of the large nanoparticle surface area, the sinteringtemperatures for the material are reduced below that of a bulk material.The dielectric film formed in accordance with these teachings isdistinguishable from a film formed by conventional depositiontechniques.

Important aspects of the present invention include the solution phaseprefabrication of size uniform (monodisperse),ferroelectric/high-dielectric nanoparticles which are subsequently“assembled from solution” to form a closed packed dielectric particlearray which in turn may be sintered or annealed to bring out the optimumproperties. These key attributes can be easily detected. A routine highresolution transmission electron microscope or high resolution scanningelectron microscope study of a cross-section of a structure will showthe following:

(1) The grain-size distribution, and whether it conforms to a Gaussiandistribution of sizes or a log normal distribution characteristic ofother physical deposition methods. The film structure for a filmfabricated in accordance with the present invention has an anomalouslynarrow grain-size distribution (i.e., less than about 15% standarddeviation) which conforms to a Gaussian distribution of sizes, and notthe log normal distribution characteristic of other physical depositionmethods.

(2) The characteristic undercutting grains (i.e., dramatic prior toannealing/sintering and still distinctive after) at the dielectricfilm-substrate interface looks significantly different from the morehemispherical particles formed by physical deposition processes andsol-gel possesses, in which the particles conform much more closely tothe substrate. The grains of the present invention may exhibit acharacteristic near-spherical shape.

In addition, the film thickness and grain size are precisely controlledby the diameter of the particles formed in solution. Thicker films canbe made by repeating the present method multiple times.

The numerous advantages of this technique, and the improvements itoffers over more conventional approaches to making thin films ofcrystalline dielectrics are as follows. This technique offers precisecontrol of the film grain size (down to ˜1 nm), which aids in theformation of thin insulating dielectrics, and is beneficial to theirintegration into nanometer-scale device structures. Additionally, forthe case of ferroelectric films, the orientation of the grains can becontrolled, and one may thus align the ferroelectric polarization in themost desirable direction. Significantly, the formation of the correctcrystal phase is done in solution, completely separate from the rest ofthe silicon circuit. High temperature annealing therefore does notimpact the performance of the circuit, as the dielectric film isdeposited into the circuit at low temperature and in the proper phase.

Using the methods of the present invention, closely packed nanoparticlethin films are obtained in which the density of nanoparticles is in therange of about 50% to about 100%. Preferably, the range is about 90% toabout 100% for heat treated thin films (relatively high dielectricresponse) and about 50% to about 60% for non-heat treated films ormonolayers (relative low dielectric response), the remainder beingcomposed primarily of organic material.

The present invention exploits the realization by the inventors that onecan take the properties of the nanoparticles and produce a film withthose same properties, and furthermore the processing conditionsrequired to generate such a film may be advantageous compared to othermethods.

It should be understood that the foregoing description is onlyillustrative of the present invention. Various alternatives andmodifications can be devised by those skilled in the art withoutdeparting from the invention. Accordingly, the present invention isintended to embrace all such alternatives, modifications and variancesthat fall within the scope of the appended claims. Therefore, if theapplication calls for an electrically-conductive film (for example)rather than dielectrics, then if the nanoparticles are electricallyconductive, the film can be made conductive.

In addition, a field effect transistor of the present invention isformed by use of the crystalline dielectric thin film as describedabove, in combination with a thin layer of organic, hybridorganic-inorganic, or inorganic semiconductor, or a semiconducting filmformed of nanoparticles. In such a device an electric field is appliedacross the dielectric film in order to modulate the conductance of thesemiconductor.

The field effect transistor may be formed, for example, by assemblingthe dielectric film on an electrically conductive substrate as a blanketcontinuous film by any of the means described herein, or by imprintlithography, screen printing, or inkjet printing as a patterned film.The deposited film may then be annealed to improve the dielectricproperties.

Once the dielectric has been formed a semiconducting layer of organic,hybrid organic-inorganic, or inorganic semiconductor, or a semiconductornanoparticle film can be deposited from the vapor phase, or solutiondeposited as a blanket film, or may be deposited by imprint lithography,screen printing, or inkjet printing to produce a patterned film. Thesemiconducting film may also be annealed to improve its electronicproperties. At least two top contacts may then be formed in order toprovide source and drain contacts.

Alternatively, the field effect transistor incorporating the dielectricfilm may be produced by first forming source and drain electrodes on anon-conducting rigid or flexible substrate (optimally SiO₂ or apolymeric material). The semiconducting organic, hybridorganic-inorganic, or inorganic semiconductor or semiconductornanoparticle film can be deposited from the vapor phase or from solutionas a continuous blanket film, or may be deposited as a patterned film byimprint lithography, screen printing or inkjet printing. Thesemiconductor film may be annealed to improve its electronic properties.

The dielectric film is then deposited on top of the semiconductor eitheras a blanket film by the means described herein, or by imprintlithography, screen-printing or inkjet printing as patterned film. Thedeposited dielectric film may be annealed to improve its dielectricproperties. Once the dielectric film has been formed, a top gateelectrode can be formed by deposition of a conductive material on top ofthe dielectric film.

A capacitor according to the present invention is formed by use of thecrystalline dielectric thin film as described above, in combination withthin layers of organic, hybrid organic-inorganic, or inorganic metallic,or a metallic film formed of nanoparticles. In such a device a voltageis applied across the dielectric film in order to store an electriccharge in the capacitor.

The capacitor may be formed, for example, by assembling the dielectricfilm on an electrically conductive bottom electrode layer as a blanketcontinuous film by any of the means described herein, or by imprintlithography, screen printing, or inkjet printing as a patterned film.The deposited dielectric film may then be annealed to improve thedielectric properties. The bottom electrode layer may be formed oforganic, hybrid organic-inorganic, or inorganic metallic, or a metallicfilm formed of nanoparticles.

Once the dielectric has been formed, a top metal electrode layer oforganic, hybrid organic-inorganic, or inorganic metal, or a metalnanoparticle film can be deposited from the vapor phase, or solutiondeposited as a blanket film, or may be deposited by imprint lithography,screen printing, or inkjet printing to produce a patterned-film. The topmetal electrode film may also be annealed to improve its electronicproperties.

What is claimed is:
 1. A method for fabricating a thin film on asubstrate, which comprises: depositing a plurality of nanoparticlesinitially in a solvent onto said substrate in such a way that saidnanoparticles form a monolayer on said substrate; wherein saidnanoparticles are coated with an organic surfactant, and wherein saidnanoparticles are electrically insulating with relative dielectricconstant greater than
 10. 2. The method of claim 1, wherein a percentageof said thin film comprised of said nanoparticles is in a range of about50% to about 100%.
 3. The method of claim 1, wherein said nanoparticleshave a diameter size in the range between about 2 nm to about 20 nm. 4.The method of claim 3, wherein a distribution of said diameter size insaid thin film has a standard deviation selected from the groupconsisting of: less than 15%, less than 10% and less than 5%.
 5. Themethod of claim 1, wherein said monolayer of nanoparticles issubsequently heated.
 6. The method of claim 1, wherein saidnanoparticles are composed of a perovskite-type oxide having the formulaABO₃, wherein A is at least one additional cation having a positiveformal charge in the range between about 1 to about 3; and wherein B isat least one acidic oxide having a metal selected from the groupconsisting of: Group IVB, VB, VIB, VIIB, IIIA, and IB.
 7. The method ofclaim 1, wherein said nanoparticles are a pervoskite-type oxide selectedfrom the group consisting of: a titanate-based ferroelectric, amanganate-based material, a cuprate based material, a tungstenbronze-type niobate, tantalate or titanate, or a layer bismuthtantalate, niobate, or titanate.
 8. The method of claim 1, wherein saidnanoparticles are a ferroelectric material selected from the groupconsisting of: bismuth titanate, strontium bismuth tantalite, strontiumbismuth niobate, strontium bismuth tantalite niobate, lead zirconatetitanate, lead lanthanum zirconate titanate, lead titanate, bismuthtitanate, lithium niobate, lithium tantalite, strontium rhuthenate,barium titanite, strontium titanate and compositions of these materialsmodified by incorporation of a dopant.
 9. The method of claim 1, whereinsaid nanoparticles are formed via a non-aqueous chemical process thatinjects metal oxide precursors at temperatures in a range between about60° C. to about 300° C.; or where said precursors are added at lowtemperature and then heated to between about 60° C. and about 300° C.10. The method of claim 1, wherein said nanoparticles are formed in apredetermined crystalline phase by either synthesizing or heating. 11.The method of claim 5, wherein said heating of said nanoparticles iscarried out at temperatures in the range between about 100° C. to about800° C.
 12. The method of claim 5, wherein said heating of saidnanoparticles is carried out at temperatures in a range between about300° C. to about 650° C.
 13. The method of claim 5, wherein said heatingof said nanoparticles is carried out using irradiation from a sourceselected from the group consisting of: laser, microwave, electron beamand ion beam.
 14. The method of claim 5, further comprising the step ofrepeating said depositing and heating steps, thereby increasingthickness of said thin film.
 15. The method of claim 1, furthercomprising the step of depositing said nanoparticles initially in saidsolvent on a liquid subphase.
 16. The method of claim 15, furthercomprising evaporating said solvent deposited on said liquid subphase,thereby forming said monolayer of said nanoparticles packed closely at aliquid-air interface of said liquid subphase, and wherein saiddepositing step transfers said monolayer of nanoparticles to saidsubstrate.
 17. The method of claim 16, wherein a percentage of said thinfilm comprised of said nanoparticles is in a range of about 25% to about75%.
 18. The method of claim 5, wherein said heating step removes saidsurfactant.
 19. A thin film fabricated on a substrate by the methodwhich comprises: depositing a plurality of nanoparticles initially on asolvent onto said substrate in such a way that said nanoparticles form amonolayer on said substrate; wherein said nanoparticles are coated withan organic surfactant, and wherein said nanoparticles are electricallyinsulating with relative dielectric constant greater than
 10. 20. Thethin film of claim 19, wherein a percentage of said thin film comprisedof said nanoparticles is in a range of about 50% to about 100%.
 21. Thethin film of claim 19, wherein said nanoparticles have a diameter sizein the range between about 2 nm to about 20 nm.
 22. The thin film ofclaim 21, wherein a distribution of said diameter size in said thin filmhas a standard deviation selected from the group consisting of: lessthan 15%, less than 10% and less than 5%.
 23. The thin film of claim 19,wherein said monolayer of nanoparticles is subsequently heated.
 24. Thethin film of claim 19, wherein said nanoparticles are composed of aperovskite-type oxide having the formula ABO₃, wherein A is at least oneadditional cation having a positive formal charge in the range betweenabout 1 to about 3; and wherein B is at least one acidic oxide having ametal selected from the group consisting of: Group IVB, VB, VIB, VIIB,IIIA, and IB.
 25. The thin film of claim 19, wherein said nanoparticlesare a pervoskite-type oxide selected from the group consisting of: atitanate-based ferroelectric, a manganate-based material, a cupratebased material, a tungsten bronze-type niobate, tantalate or titanate,or a layer bismuth tantalate, niobate, or titanate.
 26. The thin film ofclaim 19, wherein said nanoparticles are a ferroelectric materialselected from the group consisting of: bismuth titanate, strontiumbismuth tantalite, strontium bismuth niobate, strontium bismuthtantalite niobate, lead zirconate titanate, lead lanthanum zirconatetitanate, lead titanate, bismuth titanate, lithium niobate, lithiumtantalite, strontium rhuthenate, barium titanite, strontium titanate andcompositions of these materials modified by incorporation of a dopant.27. The thin film of claim 19, wherein said nanoparticles are formed viaa non-aqueous chemical process that injects metal oxide precursors attemperatures in a range between about 60° C. to about 300° C., or wheresaid precursors are added at low temperature and then heated to betweenabout 60° C. to about 300° C.
 28. The thin film of claim 19, whereinsaid nanoparticles are formed in a predetermined crystalline phase byeither synthesizing or heating.
 29. The thin film of claim 23, whereinsaid heating of said nanoparticles is carried out at temperatures in therange between about 100° C. to about 800° C.
 30. The thin film of claim23, wherein said heating of said nanoparticles is carried out attemperatures in a range between about 300° C. to about 650° C.
 31. Thethin film of claim 23, wherein said heating of said nanoparticles iscarried out using irradiation from a source selected from the groupconsisting of: laser, microwave, electron beam and ion beam.
 32. Thethin film of claim 23, further comprising the step of repeating saiddepositing and heating steps, thereby increasing thickness of said thinfilm.
 33. The thin film of claim 19, further comprising the step ofdepositing said solution on a liquid subphase.
 34. The thin film ofclaim 33, further comprising the step of evaporating said solventdeposited on said liquid subphase, thereby forming said monolayer ofsaid nanoparticles packed closely at a liquid-air interface of saidliquid subphase, and wherein said depositing step transfers saidmonolayer of nanoparticles to said substrate.
 35. The thin film of claim34, wherein a percentage of said thin film comprised of saidnanoparticles is in a range of about 25% to about 75%.
 36. The thin filmof claim 23, wherein said heating step removes said surfactant.
 37. Themethod of claim 1, wherein a percentage of said monolayer comprised ofsaid nanoparticles is in a range of about 50% to about 60%.
 38. Themethod of claim 5, wherein a percentage of said thin film comprised ofsaid nanoparticles is in a range of about 90% to about 100%.
 39. Themethod of claim 16, wherein a percentage of said monolayer comprised ofsaid nanoparticles is in a range of about 50% to about 60%.
 40. The thinfilm of claim 19, wherein a percentage of said monolayer comprised ofsaid nanoparticles is in a range of about 50% to about 60%.
 41. The thinfilm of claim 23, wherein a percentage of said thin film comprised ofsaid nanoparticles is in a range of about 90% to about 100%.
 42. Thethin film of claim 23, wherein a percentage of said monolayer comprisedof said nanoparticles is in a range of about 50% to about 60%.